Coaxial integral heating fusing belt

Abstract

A rapid warm-up fuser belt (and fusers and marking machines that use such a fuser belt) comprised of a conductive substrate having a resistive heating layer on one side and a release layer on the other side. The fuser belt further enables an electrical contact to the conductive substrate. Electrical current passing through the conductive substrate and through the resistive heating layer, causes the resistive heating layer to heat. The fuser belt can either provide for a direct electrical connection to the resistive heating layer, or it can include a semiconductive layer on the resistive heating layer that improves the electrical connection to the resistive heating layer.

We claim: 
     
       1. A fusing belt comprised of: a metallic substrate have a first surface and a second surface:   a resistive layer disposed on said first surface;   a release layer comprised disposed on said second surface; and   a semiconductive layer disposed on said resistive layer.   
     
     
       2. The fusing belt according to claim 1, wherein said resistive layer is comprised of a high temperature material. 
     
     
       3. The fusing belt according to claim 1, wherein said resistive layer includes electrically conductive particles. 
     
     
       4. The fusing belt according to claim 1, wherein said conductive substrate includes nickel. 
     
     
       5. The fusing belt according to claim 1, wherein said conductive substrate includes stainless steel. 
     
     
       6. The fusing belt according to claim 1, wherein said conductive substrate includes aluminum. 
     
     
       7. A fuser comprised of: a fusing belt member comprised of a metallic substrate have a first surface and a second surface, a resistive layer disposed on said first surface, and a release layer disposed on said second surface;   a contact roller in electrical contact with said fusing belt;   an electrical connection in electrical contact with said metallic substrate;   an electrical source, operatively connected to said contact roller and to said electrical connection, said electrical source for sending electrical current through said resistive layer such that said resistive layer heats said fusing belt; and   a semiconductive layer over said resistive layer.   
     
     
       8. A fuser according to claim 7, further including a pressure roller adjacent said release layer, said pressure roller for forming a fusing nip with said fusing belt. 
     
     
       9. The fuser according to claim 7, wherein said resistive layer is comprised of a fluoropolymer. 
     
     
       10. The fuser according to claim 7, wherein said resistive layer includes electrically conductive particles. 
     
     
       11. The fuser according to claim 7, wherein said contact roller is comprised of a thermally insulating material. 
     
     
       12. The fuser according to claim 11, wherein said thermally insulating material includes a ceramic. 
     
     
       13. The fuser according to claim 11, wherein said contact roller includes a conductive surface for providing electrical contact with said fuser belt. 
     
     
       14. A printing machine, comprising: a photoreceptor having a photoconductive surface;   a charging station for charging said photoconductive surface to a predetermined potential;   an exposure station for exposing said photoconductive surface to produce an electrostatic latent image on said photoconductive surface;   a developing station for depositing developing material on said electrostatic latent image so as to produce a toner image on said photoconductive surface;   a transfer station for transferring said toner image on said photoconductive surface to a substrate; and   a fusing station for fusing said toner image on said photoconductive surface to said substrate, said fusing station including: a fusing belt member comprised of a metallic substrate have a first surface and a second surface, a resistive layer disposed on said first surface, and a release layer disposed on said second surface;   a contact roller in electrical contact with said fusing belt;   an electrical connection in electrical contact with said metallic substrate;   an electrical source, operatively connected to said contact roller and to said electrical connection, said electrical source for sending electrical current through said resistive layer such that said resistive layer heats said fusing belt; and   a semiconductive layer over said resistive layer and disposed between said resistive layer and said contact roller.     
     
     
       15. The fuser according to claim 14, wherein said contact roller is comprised of a thermally insulating material. 
     
     
       16. The fuser according to claim 15, wherein said thermally insulating material includes a ceramic. 
     
     
       17. The fuser according to claim 15, wherein said contact roller includes a conductive surface for providing electrical contact with said fuser belt.